sssd-ad 5 File Formats and Conventions sssd-ad SSSD Active Directory provider This manual page describes the configuration of the AD provider for sssd 8 . For a detailed syntax reference, refer to the FILE FORMAT section of the sssd.conf 5 manual page. The AD provider is a back end used to connect to an Active Directory server. This provider requires that the machine be joined to the AD domain and a keytab is available. The AD provider supports connecting to Active Directory 2008 R2 or later. Earlier versions may work, but are unsupported. The AD provider is able to provide identity information and authentication for entities from trusted domains as well. Currently only trusted domains in the same forest are recognized. The AD provider accepts the same options used by the sssd-ldap 5 identity provider and the sssd-krb5 5 authentication provider with some exceptions described below. However, it is neither necessary nor recommended to set these options. The AD provider can also be used as an access, chpass and sudo provider. No configuration of the access provider is required on the client side. By default, the AD provider will map UID and GID values from the objectSID parameter in Active Directory. For details on this, see the ID MAPPING section below. If you want to disable ID mapping and instead rely on POSIX attributes defined in Active Directory, you should set ldap_id_mapping = False In order to retrieve users and groups using POSIX attributes from trusted domains, the AD administrator must make sure that the POSIX attributes are replicated to the Global Catalog. Users, groups and other entities served by SSSD are always treated as case-insensitive in the AD provider for compatibility with Active Directory's LDAP implementation. Refer to the section DOMAIN SECTIONS of the sssd.conf 5 manual page for details on the configuration of an SSSD domain. ad_domain (string) Specifies the name of the Active Directory domain. This is optional. If not provided, the configuration domain name is used. For proper operation, this option should be specified as the lower-case version of the long version of the Active Directory domain. The short domain name (also known as the NetBIOS or the flat name) is autodetected by the SSSD. ad_server, ad_backup_server (string) The comma-separated list of hostnames of the AD servers to which SSSD should connect in order of preference. For more information on failover and server redundancy, see the FAILOVER section. This is optional if autodiscovery is enabled. For more information on service discovery, refer to the SERVICE DISCOVERY section. ad_hostname (string) Optional. May be set on machines where the hostname(5) does not reflect the fully qualified name used in the Active Directory domain to identify this host. This field is used to determine the host principal in use in the keytab. It must match the hostname for which the keytab was issued. ad_enable_dns_sites (boolean) Enables DNS sites - location based service discovery. If true and service discovery (see Service Discovery paragraph at the bottom of the man page) is enabled, the SSSD will first attempt to discover the Active Directory server to connect to using the Active Directory Site Discovery and fall back to the DNS SRV records if no AD site is found. The DNS SRV configuration, including the discovery domain, is used during site discovery as well. Default: true ad_access_filter (string) This option specifies LDAP access control filter that the user must match in order to be allowed access. Please note that the access_provider option must be explicitly set to ad in order for this option to have an effect. The option also supports specifying different filters per domain or forest. This extended filter would consist of: KEYWORD:NAME:FILTER. The keyword can be either DOM, FOREST or missing. If the keyword equals to DOM or is missing, then NAME specifies the domain or subdomain the filter applies to. If the keyword equals to FOREST, then the filter equals to all domains from the forest specified by NAME. Multiple filters can be separated with the ? character, similarly to how search bases work. The most specific match is always used. For example, if the option specified filter for a domain the user is a member of and a global filter, the per-domain filter would be applied. If there are more matches with the same specification, the first one is used. Examples: # apply filter on domain called dom1 only: dom1:(memberOf=cn=admins,ou=groups,dc=dom1,dc=com) # apply filter on domain called dom2 only: DOM:dom2:(memberOf=cn=admins,ou=groups,dc=dom2,dc=com) # apply filter on forest called EXAMPLE.COM only: FOREST:EXAMPLE.COM:(memberOf=cn=admins,ou=groups,dc=example,dc=com) Default: Not set ad_enable_gc (boolean) By default, the SSSD connects to the Global Catalog first to retrieve users from trusted domains and uses the LDAP port to retrieve group memberships or as a fallback. Disabling this option makes the SSSD only connect to the LDAP port of the current AD server. Please note that disabling Global Catalog support does not disable retrieving users from trusted domains. The SSSD would connect to the LDAP port of trusted domains instead. However, Global Catalog must be used in order to resolve cross-domain group memberships. Default: true ad_gpo_access_control (string) This option specifies the operation mode for GPO-based access control functionality: whether it operates in disabled mode, enforcing mode, or permissive mode. Please note that the access_provider option must be explicitly set to ad in order for this option to have an effect. GPO-based access control functionality uses GPO policy settings to determine whether or not a particular user is allowed to logon to a particular host. NOTE: If the operation mode is set to enforcing, it is possible that users that were previously allowed logon access will now be denied logon access (as dictated by the GPO policy settings). In order to facilitate a smooth transition for administrators, a permissive mode is available that will not enforce the access control rules, but will evaluate them and will output a syslog message if access would have been denied. By examining the logs, administrators can then make the necessary changes before setting the mode to enforcing. There are three supported values for this option: disabled: GPO-based access control rules are neither evaluated nor enforced. enforcing: GPO-based access control rules are evaluated and enforced. permissive: GPO-based access control rules are evaluated, but not enforced. Instead, a syslog message will be emitted indicating that the user would have been denied access if this option's value were set to enforcing. Default: permissive ad_gpo_cache_timeout (integer) The amount of time between lookups of GPO policy files against the AD server. This will reduce the latency and load on the AD server if there are many access-control requests made in a short period. Default: 5 (seconds) dyndns_update (boolean) Optional. This option tells SSSD to automatically update the Active Directory DNS server with the IP address of this client. The update is secured using GSS-TSIG. As a consequence, the Active Directory administrator only needs to allow secure updates for the DNS zone. The IP address of the AD LDAP connection is used for the updates, if it is not otherwise specified by using the dyndns_iface option. NOTE: On older systems (such as RHEL 5), for this behavior to work reliably, the default Kerberos realm must be set properly in /etc/krb5.conf Default: true dyndns_ttl (integer) The TTL to apply to the client DNS record when updating it. If dyndns_update is false this has no effect. This will override the TTL serverside if set by an administrator. Default: 3600 (seconds) dyndns_iface (string) Optional. Applicable only when dyndns_update is true. Choose the interface whose IP address should be used for dynamic DNS updates. Default: Use the IP address of the AD LDAP connection dyndns_refresh_interval (integer) How often should the back end perform periodic DNS update in addition to the automatic update performed when the back end goes online. This option is optional and applicable only when dyndns_update is true. Default: 86400 (24 hours) dyndns_update_ptr (bool) Whether the PTR record should also be explicitly updated when updating the client's DNS records. Applicable only when dyndns_update is true. Default: True dyndns_force_tcp (bool) Whether the nsupdate utility should default to using TCP for communicating with the DNS server. Default: False (let nsupdate choose the protocol) krb5_use_enterprise_principal (boolean) Specifies if the user principal should be treated as enterprise principal. See section 5 of RFC 6806 for more details about enterprise principals. Default: true Note that this default differs from the traditional Kerberos provider back end. The following example assumes that SSSD is correctly configured and example.com is one of the domains in the [sssd] section. This example shows only the AD provider-specific options. [domain/EXAMPLE] id_provider = ad auth_provider = ad access_provider = ad chpass_provider = ad ad_server = dc1.example.com ad_hostname = client.example.com ad_domain = example.com The AD access control provider checks if the account is expired. It has the same effect as the following configuration of the LDAP provider: access_provider = ldap ldap_access_order = expire ldap_account_expire_policy = ad However, unless the ad access control provider is explicitly configured, the default access provider is permit. Please note that if you configure an access provider other than ad, you need to set all the connection parameters (such as LDAP URIs and encryption details) manually.